Protective collar for squeezable tubes



March 26, 19%58 R. H. A. HOPE PROTECTIVE COLLAR FOR SQUEEZABLE TUBESFiled June 7, 1966 2 Sheets-Sheet l MINT FIG. 4

INVENTOR.

REGINALD HARRIE ALFRED HOPE ATTORNEYS March 26, 1968 R. H; A. HOPE3,374,928

PROTECTIVE COLLAR FOR SQUEEZABLE TUBES Filed June 7, 1966 2 Sheets-Sheet2 .F|G.2 v 8 30 19 1o INVENTOR. REGINALD HARRIE ALFRED HOPE BYW g 7ATTORNEYS United States Patent 3,374,928 PROTECTIVE COLLAR FORSQUEEZABLE TUBES Reginald Harrie Alfred Hope, 7 W. Dean Valley Road,Islington, Ontario, Canada Filed June 7, 1966, Ser. No. 555,792 16Claims. (Cl. 222105) This invention relates to a collar for thedispensing end of a tube having a flexible tubular wall that can besqueezed to dispense the contents of the tube. The invention hasparticular use for tubes that contain paint and that are used as pensfor drawing patterns, for example patterns that resemble embroidery.

Squeezable tubes that can be used as pens are commonly provided with anelongated tubular wall of thin, flexible and deformable metal which canbe squeezed manually to force the contents of the tube through thedispensing end of the tube. The thin tubular wall is normally graspedbetween the fingers adjacent the dispensing end, and the latter ispressed against a surface on which the contents of the tube are to bedispensed. It is desirable to empty the tube from its flattened endtowards its dispensing end, but the pressure of the fingers tends todistort the thin tubular wall adjacent the dispensing end, to force thecontents of the tube from this end, and perhaps to rupture the thinwall.

It has been proposed heretofore to provide protective collars for suchtubes over the areas where they are normally grasped by the fingers, butthe collars of which I am aware have had the disadvantages that they arediflicult to remove and they fit closely to the tubular wall of the tubeand tend to score it. It is the object of this invention to provide animproved protective collar for such thin walled tubes.

A preferred embodiment of the invention is illustrated by way of examplein the accompanying drawings in which:

FIG. 1 is a perspective view of a tube with a protective collar inplace, the tube being held by the fingers in writing position;

FIG. 2 is a longitudinal sectional view through the assembled tube andcollar, showing the widest portion of the tube, with the outer surfaceof the narrowest portion of the tube (which is in a longitudinal planeat right angles to FIG. 2) indicated by phantom lines;

FIG. 3 is a transverse sectional view on the plane of line 3-3 in FIG.2; and

FIG. 4 is a longitudinal sectional View through the collar on a planealong the thickest portion of an internal land of the collar.

The drawings show a conventional metal tube having a conventional nylondispensing tip 11 through which paint from within the tube can flow inorder to draw lines 12 on a surface 13 when the tube is used in the rmanner of a pen. The tip 11 has a ball point (not shown) but itsconstruction is well known and forms no part of this invention. As shownin FIG. 2, a threaded neck 14 of the tip is screwed into the annulardispensing end 15 of the tube 10, said end consisting of a rigidfrustroconical wall 16 and an internally threaded cylindrical nose 17 onwhich a cap (not shown) can be held frictionally when the tube is not inuse.

The metal of the annular end 15 is relatively thick, so that its outercircular periphery 18 is of fixed diameter, i.e. does not normallybecome distorted during use of the tube. However the tube has a thintubular wall 19 (normally 0.0065 to 0.0075 inch thick) extending fromsaid periphery 18, and this wall is capable of being squeezed manuallyto dispense the contents of the tube through the dispensing end 15.Adjacent the end 15 the wall 19 has a generally cylindrical portion 20,but

towards the other end the tubular wall gradually widens (see FIG. 2) andflattens (in a longitudinal plane normal to FIG. 2, as indicated by thephantom lines 19') from said cylindrical portion 20 to a flattened end19a of the tube, the end 19a being formed by folding and crimping themetal of wall 19 upon itself. The tube 10 is normally made of a singlepiece of aluminum, the tubular wall 19 being deformable permanently whenit is squeezed to dispense the contents of the tube.

As shown in FIG. 1 the tube is held vertically and the tip 11 is presseddown to write. However if the fingers squeeze the wall 19, an excessiveamount of paint may be dispensed and the cylindrical wall portion 20 maybecome buckled. If heavier flow of paint is required it is preferable topress the wall 19 from its flattened end. As paint is used, the wall 19should be flattened from the closed end 19a, and the wall 19 should notbe folded or rolled upon itself, to ensure that it does not crack. Ifthe cylindrical portion 20 is deformed inwardly by the fingers, and thenoutwardly as paint is forced down by squeezing the flattened end of thetube, leaks may develop in the portion 20. To protect the portion 20against being flexed unduly, a protective collar 30 is provided.

The collar 30 is preferably made of clear transparent plastic so that itdoes not obscure any directions on the reading matter printed on theouter surface of the tubular wall 19. The collar has a generallycylindrical body 21 of approximately the same length as the generallycylindrical portion 20 of the wall 19. The body 21 has an open end 22whereby the collar can be assembled onto the tube 10 by sliding it overthe rigid annular end 15 and over the cylindrical portion 20 toencompass the latter within the collar. Opposite the open end 22 thecollar has an internal annular lip 23 the minimum or internal diameterof which is less than the fixed diameter of the periphery 18, so that asthe collar is slid over the tube the lip 23 abuts against the rigid end15 thereby limits the sliding of the collar towards the flattened end.The lip 23 thus provides an inwardly protruding stop means forpositioning the collar on the tube.

Extending longitudinally of the internal surface 24 of the body 21 arethree lands 25 (FIGS. 3 and 4) raised on the surface 24. These lands 25extend from the lip 23 (see FIG. 4) to the open end 22 where they arebevelled as at 26 to facilitate sliding the collar over the tube. Thelands 25 are spaced apart circumferentially of the internal surface 24and define flats along said surface, i.e. they define plane internalfaces substantially parallel to the axis of the generally cylindricalbody 21. With collar in place on the tube these smooth faces of thelands snugly engage the periphery 18 of the rigid annular end 15 of thetube and hold the collar frictionally on the tube, the body 21 beingincapable of appreciable circumferential expansion. The lands may alsoengage the thin wall 19 for a short distance away from the periphery 18but the entire internal surface 24 (including the flat surfaces of thelands) flares slightly from the lip 23 to the open end 22, the flarebeing suflicient that the entire internal surface can be clear of thewall 19 at the end 22 when the lip 23 abuts the rigid end 15. Thus theend 22 is not likely to score the wall 19, and the internal surface 24clears the wall 19 and the periphery 18 save for the frictionalengagement of the lands 25 at and adjacent the periphery 18. Theengagement is sufliciently snug to resist displacement of the collarrelative to the tube whereby, when the collar is gripped manually topress the dispensing end of the tube against the surface 13, normaldownward pressure on the collar will not force it longitudinally off thetube.

3 The fixed diameter of the periphery 18 is usually 0.875 inch (i.e.,twice the radius r in FIG. 3), the length of the wall 19 being about 4inches. For a tube having these dimensions, the collar 30 preferably hasthe following approximate dimensions as indicated in FIGS. 3 and 4.

Inches r 0.445 r u 0.480 t 0.008 1 1.25

where r is the radius of the surface 24 opposite the periphery 18, r isthe outside radius of the body 21 at the same location, I is the maximumthickness of the lands 25, and 1 is the length of the collar. The flareof the internal surface 24, measured by the angle a that it makes with aline parallel to the axis of the collar, is about /3 of a degree.

The internal surface makes an angle {3' of about 110 with the lip 23;this angle is less obtuse than the angle 7 between the outer surface ofthe wall 19 and the outer frusto-conical surface of the end wall 15 asviewed in FIG. 2, the latter angle normally being about 120, and thusthe points of engagement between the lands 25 and the periphery 18 arespaced a short distance longitudinally from the lip 23. It will beapparent that the points where the lands are to engage the periphery 18must lie on an imaginary circle having a diameter that is substantiallyequal to and not greater than the diameter of the periphery 18. In theexample given above, the internal surface 24 has, opposite the periphery18, an internal diameter of 2r or 0.890 inch, which is 0.015 inchgreater than the fixed diameter of the periphery 18, but since the landshave a maximum thickness of 0.008 inch they are, before the collar isapplied to the tube, tangential to an imaginary circle that is 0.001inch smaller in diameter than the periphery 18. Although the collarengages the tube sufficiently snugly to remain in place when the tube isused as shown in FIG. 1, the collar can nevertheless be pulled off thetube without difl'iculty. Because of the slight flare of the internalsurface 24, all parts of that surface (including the lands) at thelarger end 22 lie outside an imaginary circle having a diameter equal tothe periphery 18, and thus the collar slides easily at first onto thetube.

The collar is preferably a moulded cellulose acetate butyrate mouldingand extrusion composition sold by Eastman Chemical Inter-American Ltd.under the number 236A37038M2. This forms a resilient, single piececollar that is stiffened against transverse deformation by the lip 23.The cylindrical body 21 can when gripped as in FIG. 1 be deformed to aslightly oval shape, particularly at the end 22. Normally suchdeformation as does occur is slight, and the clearance between the innersurface 24 and the wall 19 prevents slight deformation of the collarfrom being transferred to the wall 19. Greater flexing of the collar maycause limited but not harmful deformation of the wall 19, the collar(with a thickness of r r =0.035 inch) being sufliciently stiff toprotect the cylindrical portion 20 of the wall 19 and preventsubstantial squeezing thereof under any pressures likely to be appliedin ordinary use of the tube and collar. The extent to which the tube canbe squeezed under the collar depends on where the flats 25 happen to belocated; if, for example, one of the flats happened to lie in the planeof FIG. 2 a smaller amount of deformation of the collar would berequired to deform the tube wall, but no flat is diametrically oppositeanother and the tendency is for the collar itself to deform rather thanto transmit pressure to the tube wall 19. The clearance between theinner surface 24 and the tube wall 19 leaves room for the latter todeform as the contents of the tube are used and the tube isprogressively flattened from its end 19a. Because the wall of the collarbody 21 is capable of flexing it can if necessary accommodate itself tosome lateral expansion of the tubular wall 19, as the latter isflattened, without cutting into the wall 19.

What I claim as my invention is:

1. A collar for a tube having an annular dispensing end with an outercircular periphery of fixed diameter and a tubular wall extending fromsaid periphery to a flattened end of the tube, the tubular wall beingcapable of being squeezed manually to dispense the contents of the tubethrough said dispensing end, the collar comprising a generallycylindrical body that is relatively undeformable as compared to saidtubular wall and that has an open end whereby the collar is slidableover said periphery and tubular wall to encompass a portion of thetubular wall within the collar, the body having an internal surface thatclears said periphery and tubular Wall save for circumferentially spacedapart lands raised on said internal surface adjacent at least the otherend of the body which lands are snugly engageable frictionally with saidperiphery of the dispensing end to resist displacement of the collarrelative to the tube whereby the collar can then be gripped manually topress the dispensing end of the tube against a surface On which thecontents of the tube are to be dispensed without forcing the collarlongitudinally off the tube, the collar being sufiiciently stiff toprotect the portion of the tubular wall that is encompassed by thecollar and prevent substantial squeezing thereof.

2. A collar as claimed in claim 1 and having at said other end of saidbody stop means protruding inwardly to abut against said annular end ofthe tube and thereby position the collar on the tube.

3. A collar for a metal tube having a rigid annular end with an outercircular periphery of fixed diameter and a tubular wall having agenerally cylindrical portion extending from said periphery, the tubularwall gradually flattening and widening from said cylindrical portion toa flattened end of the tube, the rigid annular end having a dispensingtip, and the tubular wall being permanently deformable and capable ofbeing squeezed manually to dispense the contents of the tube throughsaid tip, the collar comprising a generally cylindrical body ofapproximately the same length as said cylindrical portion, said bodyhaving an open end whereby the collar is slidable over said rigidannular end and over said cylindrical portion to encompass the latterwithin the collar, the collar having at the other end of said body aninternal annular lip with an internal diameter less than said fixeddiameter to abut against said rigid annular end and thereby limit thesliding of the collar towards said flattened end, said body having aninternal surface that clears said cylindrical portion save forcircumferentially spaced apart lands raised on the internal surfaceadjacent at least said other end of said body which lands are snuglyengageable frictionally with said periphery of the rigid annular end toresist displacement of the collar relative to the tube whereby thecollar can then be gripped manually to press the dispensing tip againsta surface on which the contents of the tube are to be dispensed withoutforcing the collar longitudinally off the tube, the collar beingincapable of appreciable circumferential expansion and beingsufficiently stiff to protect said cylindrical portion of the tube andprevent substantial squeezing thereof.

4. A collar as claimed in claim 3, wherein said lands are frictionallyengageable with said periphery at smooth land faces substantiallyparallel to the axis of said cylindrical body.

5. A collar as claimed in claim 4, wherein there are three of said landsspaced apart.

6. A collar as claimed in claim 5, wherein said faces are planesurfaces.

7. A collar as claimed in claim 6, wherein said internal surfaceadjacent said internal lip has an inner diameter approximately 0.015inch greater than said fixed diameter of said periphery and said landshave a maximum thickness of approximately 0.008 inch.

8. A collar as claimed in claim 3, wherein the points where the landsare engageable with said periphery lie on an imaginary circle having adiameter substantially equal to and not greater than said fixeddiameter.

9. A collar as claimed in claim 5, wherein all parts of the internalsurface of said cylindrical body at said open end lie outside animaginary circle having a diameter equal to said fixed diameter.

10. A collar as claimed in claim 9, wherein said cylindrical body has aslight internal flare from said other end to said open end and saidlands extend substantially the entire length of said cylindrical body.

11. A collar as claimed in claim 10, wherein said internal annular lipmakes with said internal surface an angle that is less obtuse than theangle between the outer surface of said rigid annular end and the outersurface of said tubular wall.

12. A collar as claimed in claim 5, wherein the collar consists of asingle piece of resilient plastic material.

13. A collar as claimed in claim 12, wherein the collar is slightlyflexible when gripped between the fingers but the clearance between saidinternal surface and said cylindrical portion is suflicient to preventslight deformation of the collar from being transferred to saidcylindrical portion.

14. A collar as claimed in claim 13, wherein said cylindrical body has awall thickness of approximately 0.035 inch.

15. A collar as claimed in claim 14, wherein the plastic is a mouldedcellulose acetate butyrate composition.

16. A moulded plastic collar for a tube having a rigid annulardispensing end with an outer circular periphery 0.875 inch in diameterand a tubular wall extending from said periphery to a flattened end ofthe tube, the tubular wall being capable of being squeezed manually todispense the contents of the tube through said dispensing end, thecollar comp-rising a generally cylindrical body approximately 1.25 inchlong with a slight internal flare from one end to the other, said bodybeing slidable larger end first over said periphery and tubular wall,the collar at the smaller end having an internal annular lip with aninternal diameter less than 0.875 inch to abut against said rigidannular end and thereby limit the sliding of the collar towards saidflattened end, said body having raised on its internal surface threelongitudinally extending substantially plane lands that are equallyspaced apart circumferentially and that are, when the lip a-buts againstsaid rigid annular end, snugly engageable with said periphery of therigid annular dispensing end to resist displacement of the collarrelative to the tube whereby the collar can then be gripped manually topress the dispensing end of the tube against a surface on which thecontents of the tube are to be dispensed without forcing the collarlongitudinally off the tube, the lands spacing the remainder of theinternal surface of said body approximately 0.008 inch away from thetube at said periphery, said internal flare being suflicient that theinternal surface can be entirely clear of the tubular wall.

at said larger end when the lip abuts said rigid annular end, the collarbeing resilient, incapable of appreciable circumferential expansion andsufliciently stiif to protect the tubular wall under it againstsubstantial manual deformation.

References Cited UNITED STATES PATENTS 1,927,553 9/1933 Lusher 2221832,323,865 7/1943 Barnes 222183 2,671,579 3/1954 Knoblock 22292 X3,231,156 l/l966 Schultz ZZZ-92 ROBERT B. REEVES, Primary Examiner.

HADD S. LANE, Assistant Examiner.

1. A COLLAR FOR A TUBE HAVING AN ANNULAR DISPENSING END WITH AN OUTERCIRCULAR PERIPHERY OF FIXED DIAMETER AND A TUBULAR WALL EXTENDING FROMSAID PERIPHERY TO A FLATTENED END OF THE TUBE, THE TUBULAR WALL BEINGCAPABLE OF BEING SQUEEZED MANUALLY TO DISPENSE THE CONTENTS OF THE TUBETHROUGH SAID DISPENSING END, THE COLLAR COMPRISING A GENERALLYCYLINDRICAL BODY THAT IS RELATIVELY UNDEFORMABLE AS COMPARED TO SAIDTUBULAR WALL AND THAT HAS AN OPEN END WHEREBY THE COLLAR IS SLIDABLEOVER SAID PERIPHERY AND TUBULAR WALL TO ENCOMPASS A PORTION OF THETUBULAR WALL WITHIN THE COLLAR, THE BODY HAVING AN INTERNAL SURFACE THATCLEARS SAID PERIPHERY AND TUBULAR WALL SAVE FOR CIRCUMFERENTIALLY SPACEDAPART LANDS RAISED ON SAID INTERNAL SURFACE ADJACENT AT LEAST THE OTHEREND OF THE BODY WHICH LANDS ARE SNUGLY ENGAGEABLE FRICTIONALLY WITH SAIDPERIPHERY OF THE DISPENSING END TO RESIST DISPLACEMENT OF THE COLLARRELATIVE TO THE TUBE WHEREBY THE COLLAR CAN THEN BE GRIPPED MANUALLY TOPRESS THE DISPENSING END OF THE TUBE AGAINST A SURFACE ON WHICH THECONTENTS OF THE TUBE ARE TO BE DISPENSED WITHOUT FORCING THE COLLARLONGITUDINALLY OFF THE TUBE, THE COLLAR BEING SUFFICIENTLY STIFF TOPROTECT THE PORTION OF THE TUBULAR WALL THAT IS ENCOMPASSED BY THECOLLAR AND PREVENT SUBSTANTIAL SQUEEZING THEREOF.